Not rendering in object mode
Duplication options segment is for telling Blender whether it should be rendering object itself or instances of child object assigned to it.


Parent and child has "None" selected. Objects are rendered as in viewport:



Parent has "Vert" selected in Duplication objects. It will be not visible. Only child Sphere instances will be rendered, without original Sphere. Sphere has to have "None" selected, as it do not have child objects assigned that could be duplicated.


In Your file, object has not any child nor parent, so it should be set to "None". "Only render" option is for viewport displaying only. When checked it displays only object that are selected to be rendered (camera icon in Scene Outliner - top, right panel). It is helpful for temporary clearing viewport from helper objects, grids, manipulators, lamps etc.

I uploaded a blend file with example: http://www.pasteall.org/blend/31324